FIGURE 1.

Induction of immune-related genes by BSA or active PP. Silkworm larvae were injected with 50 μl/larva of saline, BSA (66 μg/ml, 1 μm), or active PP (4 μg/ml, 1 μm), and after 3 h RNAs were extracted from hemocytes and fat body tissues. mRNA amounts of immune-related genes in hemocytes (A) and fat body (B) were analyzed by quantitative RT-PCR. mRNA quantity of each gene was normalized to that of a control gene, elongation factor 2, whose expression is not affected by injection of the samples. Furthermore, fold changes in mRNA quantities of BSA- or PP-injected groups relative to saline-injected groups were estimated and are shown on the longitudinal axis. Data represent mean ± S.D. (error bars) of four experiments. Statistical significance was determined by Student's t test (*, p < 0.05; **, p < 0.01).